| Which course does this assignment belong to | https://edu.cnblogs.com/campus/zswxy/CST2020-4 |
|---|---|
| Where are the requirements for this assignment | https://edu.cnblogs.com/campus/zswxy/CST2020-4/homework/11455 |
| The goal of this assignment | Learn how to use for Statement to achieve a specified number of cycles , Improve your ability to write and analyze code |
| Student number | 20209058 |
1.PTA Experiment assignment
from PTA Choose the topics in a group 3 You are most satisfied with the following topics , The more difficult it is to choose a topic , Higher score , Each question 2 branch , The content requirements are as follows ：
1.1 Before finding a simple interleaved sequence N Xiang He
This question requires the preparation of procedures , Calculation sequence 1 - 1/4 + 1/7 - 1/10 + ... Before N Sum of items .
1.1.1 Screenshot of experimental code
1.1.2 Data processing
Data expression : use flag It means the first one i Item symbol , The initial value is positive ,denominator It means the first one i The denominator of the item , For the initial 1,item Store the value of each item ,sum Store the accumulated value , among flag,i,denominator,N Is an integer ,item and sum Double precision floating point .
Data processing : Using assignment statements and simple four operations to calculate sum, Reuse for Cycle accumulation sum Value .
1.1.3 PTA Submit list and description
- Q1: There was a format error at the beginning of the run
- A1: Look carefully at the title, it turns out that there is no space on either side of the equal sign , Have to say ,pta It's very strict
1.2 Before the sequence of fractions N Xiang He
This question requires the preparation of procedures , Calculation sequence 2/1+3/2+5/3+8/5+... Before N Sum of items . Notice that the sequence starts from 2 Xiang Qi , The numerator of each term is the sum of the former and the denominator , The denominator is the numerator of the former .
1.2.1 Screenshot of experimental code
1.2.2 Data processing
Data expression ：z The molecule ,m The denominator ,i On behalf of each ,item Store the value of each item ,sum It's the result of the whole equation , The integer data has z,m,i,N, Floating point data has sum,item.
Data processing ： use for Statements are accumulated , utilize m=m-z To assign the value of the previous molecule to m
1.2.3 PTA Submit list and description
- Q1: I didn't see the problem clearly at first , Running result error
- A1: Read the title and code again , Original denominator assignment error , Direct will z The value of is assigned to the denominator , And then z The value of has changed
1.3 The digital pyramid
This problem requires the realization of function output n Line number pyramid .
1.3.1 Screenshot of experimental code
1.3.2 Data processing
Data expression ： take j It is expressed as the number of spaces to be output on the left side of each line ,i For each line , among i,j All are integers
Data processing : At the first for You need to nest two more for sentence , In addition, use a simple one print sentence
1.3.3 PTA Submit list and description
- Q1: In the compilation result , There has been a problem that the return value is ignored
- A1: In defining pyramid() Function time , It should be understood that the function of this function is the output pyramid , Don't do any calculations , So there is no return value
- Q2: In the run result , The pyramid structure is not output correctly
- A2: the last one printf In the sentence ,%d Forget to add a space after
2. Reading the code
Find a good code , Understand code functions , And tell us what you can learn from the code you have chosen .
as follows ： Check the price of the goods in the vending machine
- Take advantage of for Cycle through the menu , Simple and easy to understand
- break Statement can cause a program to jump out of a loop when a condition is satisfied
- switch Statement to implement multi branch structure , According to the number entered by the user , The corresponding price can be assigned to price, Make the program look simple and rigorous
- In the future, we can use this simple statement to realize some complex functions , Make the code as simple as possible
3. Learning summary
3.1 Learning progress bar
| Zhou / date | Time spent this week | Lines of code | Brief introduction of the knowledge learned | At present, there are some doubts |
|---|---|---|---|---|
| Week eight 10.19-10.25 | 10h | 30 | Simple input and output functions | nothing |
| Week 9 10.26-11.1 | 20h | 100 | Define basic data types , Correct use of format control string | nothing |
| Week 10 11.2-11.8 | 25h | 200 | for Loop and call simple mathematical functions | I don't know which functions can be called directly without defining |
3.2 Accumulate lines of code and blog words
3.3 Learn to understand
- I learned only one of them this week for Loop statement , But a lot of questions can be applied to it
- Although some problems seem complicated , But just find the key function to implement its function , Define data correctly , It's all over the place
- of c Many concepts and sentences of language have not been learned , Some of the topics are very simple , It's complicated by me , This requires me to spend more time learning
